Apparatus for forming fiber sheets



Dec. 12, 1933. H. w. PIQUET APPARATUS FOR FORMING FI'BER SHEETS FiledJan. 29, 1952 Patented Dec. 12, 1933 UNITED STATES PATENT OFFICE HenryW. Piquet, Moorestown, N. .L, assignor to MacAndrews and Forbes Company,Camden, N. 1., a corporation of New Jersey Application January 29,1932.' Serial No. 589,732

Claims.

This invention relates to new and useful improvements in apparatus foruse in the formation of relatively thick fibre sheet and particularly inthe formation of insulating sheet, wall board, or the like.

The principal object of the invention is to provide apparatus of thecharacter set forth having certain novel features of constructionaffording a fibre sheet having a substantially smooth surface texture.Another object of the invention is to provide apparatus as set forthhaving certain novel features of construction capable of -forming fibresheets of substantially greater uniformity or more dense fibrestructure.

Another object of the invention is to provide apparatus as set forthwhereby sloughing of the fibre stock from the cylinder prior toengagement by the pressure means, is eliminated.

Another object of the invention is to provide apparatus as set forthhaving a novel idling or smoothing roller.

Another object of the invention is to provide apparatus as set forthhaving novelmeans for alleviating vacua created adjacent the idling orsmoothing roller.

Another object of the invention is to provide apparatus. as set forthembodying a novel feed arrangement for the sheet stock to the machinefor the purpose of affording better agitation thereof prior to theformation of the fibre sheet.

Other features and details of the invention are disclosed hereinafterand shown in the accompanying drawing, in which:

Figure 1 is a transverse sectional view of the apparatus constitutingthe invention; and

Fig. 2 is a fragmentary view in perspective showing the novelconstruction of the idling or smoothing roller.

Referring now particularly to the drawing, the present apparatusembodies a conventional form of cylinder machine comprising a vat 1carrying the stock in which rotates the forming cylinder 2.

The interior of the forming cylinder is equipped with customary" suctionapparatus by means of which the degree and application of suction invarious regions on the surface of the cylinder may be controlled. Thesuction apparatus is of usual construction and need not be illustratedand described in detail. A continuous wire'belt 3 is provided and iscarried by the rollers 4 and the idling roll 5 for the purpose ofpressing the wet web to extract the water therefrom and to substantiallysmooth the surface texture of said web by the suction in said cylinder,that is, the amount in advance of the point where the web leaves thecylinder.

In the present instance the particular feature of the invention residesin positioning the idling roller 5 entirely below the surface of thestock in the vat 1. By positioning the idling roller 5 B0 in the mannerset forth, the fibres of the wet web ultimately formed will be laid andthe texture of the web formed, prior to emerging from the vat. The wetweb produced in the above manner embodies a body structure of greateruniformity and fibre density having an extremely smooth surface texture,than similar machines have been capable of producing heretofore.Furthermore, by positioning the idling roller 5 below the surface of thestock, there is no interval, prior 7 to the contact of the belt 3 withthe wet web, after the web emerges from the vat 1, to permit a tendencyfor the stock to slough back into the vat from the cylindenas in amajority of machines. The roller 5 in the present instance is sopositioned, radially of the cylinder 2, as to effect a gradualapplication of the pressure of the wire belt 3 upon the web, just priorto emerging from the vat 1, on the cylinder 2, thus eliminating thesudden application of the total pressure of the belt, which tends todestroy the already formed surface texture of the wet web and is mostundesirable.

It has been found, by positioning the ordinary cylindrical roller havinga solid surface, beneath 5 the surface of the sheet stock, there is atendency for said stock to become lodged within the roller,necessitating periodic removal thereof for purposes of cleaning. Toeliminate the above undesirable feature, a roller or pulley of the typedisclosed in Fig.2 of the drawings is positioned beneath the surface ofthe stock. This roller or pulley designated generally as at 5 is ofrelatively open construction having the spaced longitudinal members 6thereof disposed with respect to the shaft '7 by means of the spokes 8.By the construction set forth the stock mix residing about the roller 5is kept in continuous agitation which prevents the said stock becomingdry and adhering to the roller. A shower or spray 9 is disposed abovethe roller 5 and functions to flush any stock in said roller back intothe vat proper.

The spray or shower 9 functions in a second capacity to dilute the stockin the vat adjacent the pulley 5 and eliminate any tendency for said 105stock becoming to viscous, due to lack of water content which has atendency to be drawn from said stock, through the web on the cylinder 2,

of water supplied to the stock by the shower 9 must be sufiicient tocompensate for the water drawn from the stock by the suction, in orderthat the stock adjacent the pulley 5 will be mainroller 5 and the wirebelt 3 along a course adja' cent the inner surface of the vat 1 to theposition where the stock adheres to the surface of the cylinder 2 by theaction of the suction internally thereof.

Fibre web formed in the manner, and by means of the apparatus, hereindisclosed, is of greater uniformity and of relatively smoother surfacetexture than has heretofore been obtainable, and affords a product ofmore finished appearance and greater desirability in the open market.

While a particular embodiment-of the invention has been disclosed hereinfor the purpose of description, it is not intended to be limited theretoexcept as set forth in the appended claims.

I claim:

1. Apparatus for forming a fibre web from substantially viscous stockcomprising in combination, a stock vat, a suction forming cylinderarranged for rotation and forming a continuous wet web of substantialthickness, a skeleton return roll mounted for rotation in the vet at apoint below the surface level of the stock therein, and means passingabout said roll contacting with the web for a predetermined length oftravel beginning at a.poi nt' below .the surface of r the stock in thevat.

2. Apparatus for forming a fibre web from substantially viscous stockcomprising in combination, a stock vat, a suction forming cylinderarranged for rotation and forminga continuous wet web of substantialthickness, a skeleton return roll mounted for rotation in the vat at apoint below the surface level of the stock therein, the said roll beingof substantially open construction whereby clogging'of the roll by thestock is precluded, and means passing about said roll contacting withthe web for a predetermined length of travel beginning at a point belowthe surface of the stock-in the vat.

3. Apparatus for forming a fibre web from substantially viscous stockcomprising in combination, a stock vat, a suction forming cylinderarranged for rotation and forming a continuous wet web of substantialthickness, a skeleton return roll mounted for rotation in the vat at apoint below the surface level of the stock therein, the said roll beingof substantially open construction whereby clogging of the roll by thestock is precluded, and water passable means passing about said rollcontacting with the web for a predetermined length'of travel beginningat a point below the surface of the stock in the vat.

4. Apparatus for forming a fibre web from substantially viscous stockcomprising in combination a stock vat, a, suction forming cylinderarranged for rotation and forming a continuous wet web of substantialthickness, a skeleton return roll mounted for rotation in the vat at apoint below the surface level of the stock therein, the said roll beingof substantially open construction whereby clogging of the roll by thestock is precluded, and pressure means passing about said rollcontacting with the web for a predetermined length of travel beginningat a point below the surfaceof the stock in the vat, the said pressuremeans being arranged to gradually apply pressure to said web and preventsloughing of the stock from the surface of the cylinder to the vat.

5. Apparatus for forming a fibre web from substantially viscous stockcomprising in combination a stock vat, a suction forming cylinderarranged for rotation and forming a continuous wet web of substantialthickness, a skeleton return roll mounted for rotation in the vat at apoint below the surface level of the stock therein, the said roll beingof substantially open construction whereby clogging of the roll bythestock is precluded, water passable means passing about said rollcontacting with the web for a predetermined length of travel beginningat a point below the surface of the stock in the vat, and means adjacentone end of said pressure means to defleet stock fed to-said vat from thepath of said pressure means.

HENRY W. PIQUET.

